Qualcomm wants to beam signals to airplanes from 150 ground stations.

The Federal Communications Commission (FCC) next Thursday will consider a plan to beam Internet signals up to airplanes from 150 ground stations operating in a spectrum band already used by satellites. Qualcomm has proposed such a service in the 14.0-14.5GHz band but faces opposition from the satellite industry, which says the service is unnecessary and would interfere with satellite transmissions.

Qualcomm's proposal came in July 2011 and is now on the verge of moving forward. The FCC's meeting on Thursday "will consider a Notice of Proposed Rulemaking [NPRM] seeking to improve consumer access to broadband aboard aircraft and encourage innovation through establishment of an Air-Ground Mobile Broadband secondary service in the 14.0-14.5 GHz band, while ensuring that existing users are protected from interference."

This isn't the final step. If approved, the NPRM will be followed by extensive debate, public comment, and likely testing to determine whether interference concerns are valid. Already, the Satellite Industry Association (SIA) and others using the spectrum band say Qualcomm's proposal should be rejected or heavily restricted.

Qualcomm’s plan is wonderful, according to Qualcomm

First, let's take a look at what Qualcomm wants. It is essentially asking to become the exclusive provider of backhaul to airlines or in-flight ISPs like Gogo in the 14.0-14.5GHz band through a secondary license that shares the spectrum with the band's incumbents. Just in case the FCC doesn't want to give the license only to Qualcomm, the company said it would also support an auction that splits the airwaves among two backhaul providers.

"Qualcomm proposes that the Commission would conduct an auction of two 250MHz licenses at 14.00 to 14.25GHz and 14.25 to 14.50GHz to enable two separate systems, but not restrict a single entity from purchasing both licenses to construct a single, more robust, 500MHz system," Qualcomm said in its proposal. "The proposed system would support communications between terrestrial ground stations and aircraft, much like the current Aircell Air-Ground system, but with significantly greater bandwidth to support the exponentially increasing data demands of today's consumers who require anywhere/anytime broadband access including when they are flying in a plane several miles above the surface of the earth."

Qualcomm acknowledged interference concerns but said it can work around them. The system would use about 150 ground stations to provide 300Gbps capacity to airlines. "The proposed Next-Gen AG system would operate in the Ku band at 14.0 to 14.5 GHz on a secondary licensed basis to, and in successful coexistence with, Geosynchronous Orbit ('GSO') satellite systems (used to provide various services, including Qualcomm's own OmniTRACS service), future Non-Geosynchronous Orbit ('NGSO') satellite systems, NASA's Tracking and Data Relay Satellite System ('TDRSS'), and radio astronomy users. Indeed, as an incumbent user of this band itself, Qualcomm has a direct interest in fully protecting incumbent operations," the company wrote.

Qualcomm described several tactics to minimize interference. For example, all ground stations "will have high antenna gain to permit aircraft to transmit at very low power levels." Moreover, "aircraft will use directional receive antennas to reduce the GS [ground station] transmit power needs."

"Finally, the Next-Gen AG system will hand-off aircraft communications to successive GSs that track the aircraft's flight path and in this way work in a manner similar to terrestrial cellular networks," Qualcomm said. "These aircraft communications handoffs will allow the system to operate successfully through using the least amount of transmit power to maintain a desired Carrier-to-Noise interference ratio and a negligible TfT (also referred to as Rise over Thermal) level into GSO [geosynchronous orbit] satellite operations below 1% in all scenarios including worst case scenarios."

Qualcomm claimed the system will be robust enough to support "video streaming, gaming, and other rich multimedia access" during flights. Qualcomm declined to speak to Ars about the FCC proceeding and its proposal.

"Qualcomm’s proposed ATG [air-to-ground] system will cause interference into the FSS [Fixed Service Satellite] satellite services that are primary in that band," the Satellite Industry Association wrote in a filing yesterday. "SIA reviewed the ongoing importance of the Ku-band uplink bands to the satellite industry, noting that the industry has invested more than $20 billion to build, launch and operate more than 80 satellites with Ku-band capacity. These satellites generate more than $1 billion dollars in satellite services revenue in North America alone."

In a filing last July, the Satellite Industry Group tried to poke holes in Qualcomm's interference analysis:

Qualcomm’s technical analysis of interference from FSS into ATG airborne stations is based on a number of unsupported assumptions. Qualcomm divides the VSATs [satellite ground stations] that are located within a 300 km radius of the aircraft into two groups—those that are located north of the aircraft and those that are located south of the aircraft. With regard to the south-side VSATs, Qualcomm assumed that many VSAT installations will be fully shadowed by other buildings in direction of the receiving aircraft in estimating that only 25% of the south-side VSATs have an unobstructed view of the aircraft. These assumptions are highly subjective and Qualcomm has provided no evidence to support its assumptions.

Further, the SIA said, "Qualcomm has not shown that demand for in-flight passenger connectivity cannot be met by terrestrial or satellite-based deployments in existing frequency allocations that do not pose the same sharing difficulties as the proposed secondary ATG service."

Qualcomm says otherwise, of course. "Current in-flight communication systems are either too expensive or data capacity limited and thus will be unable to support the increasing data demands of consumers," Qualcomm's proposal states. "In contrast to the relatively low-cost terrestrial-based system proposed herein, satellite-based systems have much higher equipment costs and potentially crippling latency issues, and thus have been deployed with marginal success."

American Airlines submitted a filing supporting the Qualcomm proposal, saying, "The service will be important to satisfying air travelers' increasing demands for mobile broadband data." Delta Air Lines filed similarly positive remarks about the Qualcomm plan. "Delta believes the proposal could successfully co-exist with current and future, primary and secondary users of the 14.0 to 14.5GHz band, using the beam and power level management techniques detailed in Qualcomm’s proposal," Delta wrote.

Boeing disagrees, saying it "believes that gaps and inconsistencies in the technical information cast doubt on an ATG system’s ability to protect and tolerate interference from existing Fixed Satellite Service ('FSS') operations and future Non-Geostationary Satellite Orbit ('NGSO') operations in the band." Boeing further noted that "the Petition focuses on the intensively used 14.0-14.5GHz band in disregard of plausible alternative bands, including the similarly allocated and under-used High Altitude Platform Station (“HAPS”) spectrum at 47GHz."

Row 44, a provider of satellite Internet to Southwest and other airlines, dismissed the idea that Qualcomm's service is necessary and seems worried that Qualcomm's service would benefit Gogo. In an FCC filing, Row 44 stated:

GoGo, Inc. (“GoGo”), the principal customer for Qualcomm’s existing ATG service technology, has expressed substantial support for the proposal. Yet even GoGo’s comments raise significant questions regarding its own commitment to large-scale provision of in-flight broadband services using terrestrial ATG technology.

Specifically, GoGo indicates that it is moving toward relying on Ka-band satellite technology for the delivery of broadband services on board aircraft, but notes that “satellite may not always provide the best solution for all aircraft and all customers.”

This implied future reliance on satellite-delivered services to meet the needs of GoGo’s primary airline customers suggests that its remaining terrestrial service is expected to serve more as an adjunct for niche customers than as a primary means of broadband service delivery. This raises the question whether an additional spectrum allocation for ATG service is really needed even for GoGo’s expressed purposes.

Panasonic Avionics Corporation, an in-flight entertainment and communications company, also raised interference concerns. The National Radio Astronomy Observatory weighed in as well, saying the Qualcomm system must be built carefully to minimize direct interference with astronomy sites. "Additional restrictions to ATG operations may be necessary," the group said.

A complex decision for the FCC

Complicating matters even further, the Utilities Telecom Council and a company called Winchester Cator have proposed new smart grid and emergency communications uses for the 14.0-14.5GHz band. UTC and Winchester Cator have asked the FCC to consider its proposal alongside Qualcomm's, instead of in separate proceedings.

Promoted Comments

Qualcomm's interference avoidance plan doesn't really sound like a well engineered plan...it just sounds like turning down the power as low as they can and hoping for the best.

Quote:

all ground stations "will have high antenna gain to permit aircraft to transmit at very low power levels."

Quote:

"aircraft will use directional receive antennas to reduce the GS [ground station] transmit power needs."

Quote:

"Finally, the Next-Gen AG system will hand-off aircraft communications to successive GSs that track the aircraft's flight path and in this way work in a manner similar to terrestrial cellular networks," Qualcomm said. "These aircraft communications handoffs will allow the system to operate successfully through using the least amount of transmit power..."

Well, in addition to the low transmit power, a high amount of antenna gain indicates that the beam is very directional. A potentially-nonintuitive detail of RF propagation is that an antenna doesn't create gain by actually increasing its power output. Instead, the "gain" comes from a comparison to a theoretical isotropic radiator that emits energy uniformly in every direction. The gain comes from the fact that a directional antenna focuses its output more strongly in certain directions than others. The measured gain, therefore, is the increase in observed power at some particular orientation from the antenna when compared to what would be expected if the antenna is isotropic. So, if you have a very high-gain antenna, then most of its output is focused in one or more specific directions. This can be thought of as another interference mitigator.

With that said, I haven't read much about the proposal, so it's quite possible that it's insufficient. Similar to the LightSquared debacle, however, it sounds like a new party wanting to repurpose a band for ground use that is typically used for earth-satellite links only. It's rational for those who already use that frequency band to lobby against its use for other purposes, thus preventing even the possibility that their services could be disrupted.

34 Reader Comments

Qualcomm's interference avoidance plan doesn't really sound like a well engineered plan...it just sounds like turning down the power as low as they can and hoping for the best.

Quote:

all ground stations "will have high antenna gain to permit aircraft to transmit at very low power levels."

Quote:

"aircraft will use directional receive antennas to reduce the GS [ground station] transmit power needs."

Quote:

"Finally, the Next-Gen AG system will hand-off aircraft communications to successive GSs that track the aircraft's flight path and in this way work in a manner similar to terrestrial cellular networks," Qualcomm said. "These aircraft communications handoffs will allow the system to operate successfully through using the least amount of transmit power..."

Qualcomm's interference avoidance plan doesn't really sound like a well engineered plan...it just sounds like turning down the power as low as they can and hoping for the best.

Quote:

all ground stations "will have high antenna gain to permit aircraft to transmit at very low power levels."

Quote:

"aircraft will use directional receive antennas to reduce the GS [ground station] transmit power needs."

Quote:

"Finally, the Next-Gen AG system will hand-off aircraft communications to successive GSs that track the aircraft's flight path and in this way work in a manner similar to terrestrial cellular networks," Qualcomm said. "These aircraft communications handoffs will allow the system to operate successfully through using the least amount of transmit power..."

Well, in addition to the low transmit power, a high amount of antenna gain indicates that the beam is very directional. A potentially-nonintuitive detail of RF propagation is that an antenna doesn't create gain by actually increasing its power output. Instead, the "gain" comes from a comparison to a theoretical isotropic radiator that emits energy uniformly in every direction. The gain comes from the fact that a directional antenna focuses its output more strongly in certain directions than others. The measured gain, therefore, is the increase in observed power at some particular orientation from the antenna when compared to what would be expected if the antenna is isotropic. So, if you have a very high-gain antenna, then most of its output is focused in one or more specific directions. This can be thought of as another interference mitigator.

With that said, I haven't read much about the proposal, so it's quite possible that it's insufficient. Similar to the LightSquared debacle, however, it sounds like a new party wanting to repurpose a band for ground use that is typically used for earth-satellite links only. It's rational for those who already use that frequency band to lobby against its use for other purposes, thus preventing even the possibility that their services could be disrupted.

I foresee a lot of people saying that the quiet, disconnected time is good, and having the web unavailable for a bit may be good for you... ...but I think I'd get over that.

Me too. Anything to help relieve the boredom when flying would be welcomed by me and many others.

Honestly, this is a big reason why I demand sdMicro slots in all my devices. That and a spare battery pack and I have all the entertainment I need for even overseas flights (and I take quite a few 14+hr flights). WiFi would be nice, but I usually don't bother paying for the service even when available.

I'd think that done correctly this should be workable with minimal interference issues. I'm assuming that this is in the uplink side of KU bands. We've already got multiple sats sharing the same frequencies by spacing them out and using directional antenna's as this proposal suggests. Planes are much lower (relatively speaking compared to GSO) so can get by with much lower power. You can also position the ground stations properly so that the antenna are mostly facing away from the sats since they are all in orbit around the equator. North or even east and west facing antenna's should be safe. Southerly facing antenna's might be a little more risky but since there are regular paths that almost all flights follow that can be managed by picking proper ground station locations.

Honestly, this is a big reason why I demand sdMicro slots in all my devices. That and a spare battery pack and I have all the entertainment I need for even overseas flights (and I take quite a few 14+hr flights). WiFi would be nice, but I usually don't bother paying for the service even when available.

Me too. A couple of ebooks, a few loaded movies, an auxiliary battery for my iPad and I'm ready for the long over water flights I take (15 -19 hours).

Or the FAA could, ya know, let us use our cellphones on planes like the rest of the world, but that wouldn't make extra money for certain companies.

In other countries, people can use their GSM-based phones on the airplane.

However...

That is because there is a GSM micro-cell on board the aircraft linked by ATG or satellite links to relay your call or SMS. You aren't connected to ground cell towers in flight.

I'm all for using this spectrum for ATG communications for aircraft. I think that the current meager spectrum allocation GoGo has (4MHz) and the latency of either Ka or Ku satellite-based communications are causing people who actually use WiFi in the air to be frustrated with the quality of service.

To me, it was a bit funny that Boeing (commercial satellite arm) is in opposition, while many of their commercial aircraft customers like Delta and American Airlines are in favor of it.

At most, there are about 5,000 aircraft in the air. So 300Gbit/s is 60Mbps per aircraft if you provision every commercial aircraft with this service. Sounds like it'll be plenty fast.

If Qualcomm agrees to fully shoulder the costs of re-imbursing the satellite industry for lost income, the de-orbiting any obsoleted satellites and launch of replacements, then they would very likely meet considerably reduced opposition to their plan.

As it stands now however it looks more like Qalcomm wants to have cake and eat it at the same time. "Consumers" can be without their facking tweeters and facebonks for the scant few hours they sit in an airplane over the course of their lives. There's no logical reason to sacrifice an existing industry for the whimsical and short-sighted desire of Qualcomm's to make more money at others' expense.

The interest in this band is from present license-holders trying to wring value out of their license, right? Or is there some technical advantage to shoehorning more applications into a band already widely in-use?

So, LightSquared is part of an association that is one of the main opponents of a project that is very similar to the one they tried to implement, and failed get approval for from the FCC? And for the same reasons (harmful interference)? Isn't that a bit hypocritical?

Ample tests have been done, using nothing more than the typical 4G USB devices (Those that fall back to 3G during 4G signal loss) on non-stop coast to coast flights (NYC to LA). Not only do they yield highly acceptable results (virtually uninterrupted internet access), but no planes have fallen from the sky, no air to ground communications have been disrupted, no flight systems have suffered interference, no wireless ISP's have sent nasty-grams to the device users for wreaking havoc on their terrestrial networks. That being said, if Qualcom and their "partners" wish to invest a fortune in building out their proposed system, let them. I dare say most flyers will not be able to afford their in-flight service, and that's assuming it works, or doesn't get shut down for causing interference. The Government hogs an astronomical amount of valuable spectrum. Most of which sits unused, and has for decades.They refuse to relinquish it, even though they have no plans to use it. The solution is NOT to try and share what's out there, but get our government to cut loose some of that prime "RF real estate" and sell or auction it. Goodness knows, there's a long line of entities that will pay for it. And don't we have some budget issues to address? How about peddling the spectrum instead of dipping into the already empty pockets of those on social security and other essential government assistance that politicians refer to as "entitlements". The only people i know receiving "entitlements" are politicians. They take our money and sit around and do nothing but come up with ways to take more of our money. God it feels good to rant. :-)

Airborne directional receivers for this? Last I checked, mobile tracking systems for satellites, less sophisticated than this, were in the neighborhood of $40,000 each. They expect airlines, that charge $35 to carry a bag of clothes, will want to assume that cost?

I suppose it could be done on select long range aircraft, at confiscatory rates per minute to recoup their initial costs.

Can you provide a link to these tests? Someone Who Isnt Me never gets service when their cellphone is mistakenly left on during flights. the skin of the plane acts as a pretty good faraday's cage and the antennas on cell towers are slightly angled down. The two combine to produce very low odds of the devices reaching each other at cruising altitude.

Ample tests have been done, using nothing more than the typical 4G USB devices (Those that fall back to 3G during 4G signal loss) on non-stop coast to coast flights (NYC to LA). Not only do they yield highly acceptable results (virtually uninterrupted internet access), but no planes have fallen from the sky, no air to ground communications have been disrupted, no flight systems have suffered interference, no wireless ISP's have sent nasty-grams to the device users for wreaking havoc on their terrestrial networks. That being said, if Qualcom and their "partners" wish to invest a fortune in building out their proposed system, let them. I dare say most flyers will not be able to afford their in-flight service, and that's assuming it works, or doesn't get shut down for causing interference. The Government hogs an astronomical amount of valuable spectrum. Most of which sits unused, and has for decades.They refuse to relinquish it, even though they have no plans to use it. The solution is NOT to try and share what's out there, but get our government to cut loose some of that prime "RF real estate" and sell or auction it. Goodness knows, there's a long line of entities that will pay for it. And don't we have some budget issues to address? How about peddling the spectrum instead of dipping into the already empty pockets of those on social security and other essential government assistance that politicians refer to as "entitlements". The only people i know receiving "entitlements" are politicians. They take our money and sit around and do nothing but come up with ways to take more of our money. God it feels good to rant. :-)

Qualcomm's interference avoidance plan doesn't really sound like a well engineered plan...it just sounds like turning down the power as low as they can and hoping for the best.

Quote:

all ground stations "will have high antenna gain to permit aircraft to transmit at very low power levels."

Quote:

"aircraft will use directional receive antennas to reduce the GS [ground station] transmit power needs."

Quote:

"Finally, the Next-Gen AG system will hand-off aircraft communications to successive GSs that track the aircraft's flight path and in this way work in a manner similar to terrestrial cellular networks," Qualcomm said. "These aircraft communications handoffs will allow the system to operate successfully through using the least amount of transmit power..."

Well, in addition to the low transmit power, a high amount of antenna gain indicates that the beam is very directional. A potentially-nonintuitive detail of RF propagation is that an antenna doesn't create gain by actually increasing its power output. Instead, the "gain" comes from a comparison to a theoretical isotropic radiator that emits energy uniformly in every direction. The gain comes from the fact that a directional antenna focuses its output more strongly in certain directions than others. The measured gain, therefore, is the increase in observed power at some particular orientation from the antenna when compared to what would be expected if the antenna is isotropic. So, if you have a very high-gain antenna, then most of its output is focused in one or more specific directions. This can be thought of as another interference mitigator.

With that said, I haven't read much about the proposal, so it's quite possible that it's insufficient. Similar to the LightSquared debacle, however, it sounds like a new party wanting to repurpose a band for ground use that is typically used for earth-satellite links only. It's rational for those who already use that frequency band to lobby against its use for other purposes, thus preventing even the possibility that their services could be disrupted.

I apologize for the length of this post up front!

If you look at the proposed instantiation you will see that while Qualcomm claims the ground antennas are very directional, they are not. The pattern is a classical cell pattern based upon hex cells thus the half power beamwidth of the ground antennas have to be at least 60 degrees (and Qualcomm admits this in some of its later filings -- even though Qualcomm tries to put forth that this wide beamwidth is more than directional enough).

The biggest issue is that NO ONE has done a full and complete interference analysis. They are very detailed and cost a LOT of money to do. I personally did one back in the 90s (with some help from various experts as necessary) that ended up being about 800 pages long. Qualcomm has done a partial interference analysis several times but never a complete, detailed one -- and the sum of all the interference analyses done so far does not add up to one complete one. The satellite organizations have done a few themselves showing different results. The FCC needs to *require* Qualcomm to submit a FULL, DETAILED interference analysis or else kill this.

Last I checked Qualcomm was not willing to state the precise radiation patterns of the ground and airborne antennas to be used in the system. Instead they are using generic patterns based upon what any undergrad could get out of a textbook. As anyone who has gone through various certifications can tell you, even the best antennas have patterns that can be radically different from the textbooks with off axis peaks that don't conform to the textbook sidelobe patterns. Additionally, Qualcomm won't detail the backside power emissions. (Yes, even on a parabolic dish there is energy radiated in the opposite direction.)

Even with a submission of a full, detailed interference analysis by Qualcomm there are still several possible issues.

Once the FCC allocates for Aeronautical Mobile in the 14-14.5 GHz band it will very likely auction off that spectrum. There is a significant chance that Qualcomm will not win that auction. The winner may not design or install a system identical to Qualcomm's currently proposed design. Hell, even if Qualcomm wins the auction there is a significant chance that Qualcomm's final implementation will not precisely follow the currently proposed design!

How does Qualcomm propose to handle spurious transmissions from equipment? It happens. This has not been addressed in any filings of which I am aware.

The list goes on and on.

What should the FCC do?

It's literally "Put up or shut up" time.

First, they should require Qualcomm to submit a full, detailed interference analysis that includes all players with a current allocation in that frequency band. It also must include not only current systems but also all other systems that have been filed as of 1 June 2013 with the NTIA, FCC and ITU for fielding within the next 5+ years. This analysis must be completed no later than 1 August 2013 and filed no later than 2 August 2013. (Historically, it has been standard practice for the FCC to give a petitioner 60 days to file an interference analysis once requested.) Qualcomm must clearly show that their proposed system will not interfere with any system currently fielded or that will be fielded under the currently authorized allocations.

Second, protests must be filed no later than 15 December 2013. If an organization (or consortium of organizations) wants to protest, they need to file a full, detailed interference analysis of their own. It must be every bit as detailed as the one required to be produced by Qualcomm. The protestors must extremely clearly show why they think their analysis is correct and Qualcomm's analysis is wrong. The protestors must clearly show that Qualcomm's system will interfere with systems fielded under the current allocations. There can be no "it might interfere if xyz were to occur". The 15 December 2013 date gives the protestors two months to review Qualcomm's analyses and another two months to perform their own analyses (plus a little extra time for September through November holidays).

Finally, if the analyses show extremely little or no possibility of interference then the FCC should grant the new allocation under an Aeronautical Mobile allocation (NOT a generic Mobile allocation) and on a secondary basis only. Secondary allocations cannot interfere with primary allocations. If a primary user can definitively show that a secondary user is interfering with the primary's service the FCC has the authority to shut the secondary service down in part, or in its entirety, until the issue is resolved. If the issue cannot be resolved, the FCC has the authority to shut the secondary service down permanently.

If Qualcomm is so sure that its system will not interfere with the currently allocated primary users then Qualcomm should have no problem with this secondary allocation. Additionally, this secondary allocation gives a safety net to the current users. Then, if after 5+years of Qualcomm's system being fully operational there have been no substantiated claims of interference by Qualcomm's system into the currently allocated systems, Qualcomm can petition for the allocation to go from secondary to primary. The FCC could than grant primary allocation status.

So let me get this straight. Boosting in-flight internet = ok, but FAA regulations dictate that I can't even use my Kindle on take-off/landing? Makes perfect sense!

Off topic: show

The FAA regulations concerning powering-off devices at take-off and landing have less to do with radio interference, but rather more to do with distractions from crew instructions, in the rare event of an emergency.